When an assistant message with toolCalls has stopReason 'aborted' or 'error',
the guard should not add those tool call IDs to the pending map. Creating
synthetic tool results for incomplete/aborted tool calls causes API 400 errors:
'unexpected tool_use_id found in tool_result blocks'
This aligns the WRITE path (session-tool-result-guard.ts) with the READ path
(session-transcript-repair.ts) which already skips aborted messages.
Fixes: orphaned tool_result causing session corruption
Tests added:
- does NOT create synthetic toolResult for aborted assistant messages
- does NOT create synthetic toolResult for errored assistant messages
8db7ca8c02